Nobody who lives on the Upper West Side is driving to work. They circle looking for spots when they have to move their cars for street cleaning and when the get back Sunday night from their country houses.
as an UWSer who does not know anyone with a "country residence" or who can afford a second residence at all given the exorbitant price of living in this city, there are plenty of other reasons for people to take the car out in the middle of the day on a summer weekend like, say, going to a beach with your chairs and cooler etc which isn't something you can do with public transit, or going hiking someplace not right off a train line, or any number of things that ordinary non-super-rich people do.
Sure, but every time NYC "car culture" questions come up, people start wringing their hands about people who need to drive to work. If we're talking NYC that's a low percentage of people who do drive to work (whether they need to is another question) and for the Upper West Side (say, zipcodes 10023, 10024, 10025) very low, 6%-7%.
I would certainly support resident parking permits. I don't think many people need to commute into the UWS for work by car, since of course the entire neighborhood is hooked up to transit endpoints that have their own parking, which is not necessarily true for the places that UWSers commute to.
Cars are prevalent because they take up a lot of space, but car ownership is not. Not even 25% of people in Manhattan own car. Even in Staten Island 17% of people don't have a car.